The double-vision display technology is one in which a slit grating is attached in front of a display unit such that viewers from different angles can see different images on the same display. FIG. 1 is a schematic view of the display principals of an existing double-vision display technology, and FIG. 2 is a schematic view of an existing double-vision display structure. As shown in the figures, the double-vision display structure 100 comprises a display unit 70 and a slit grating 80 provided in front of the display unit, the distance between which is h, and this distance h is referred to as a predetermined height. Odd sub-pixel columns 72-1 on the display unit 70 display one image, and even sub-pixel columns 72-2 display another image. Each opening of the slit grating 80 is arranged between adjacent odd and even sub-pixel columns. As long as the predetermined height h is appropriate, a viewer can see the image displayed by even sub-pixel columns on the left side of the double-vision display, which forms a left vision area, while can see the image displayed by odd sub-pixel columns on the right side of the double-vision display, which forms a right vision area; and the intermediate part can be seen on both sides, which forms a crosstalk area.
There are at least the following problems in the existing technology. The width of a sub-pixel on the existing display unit 70 is typically about 50 microns. In order to achieve big enough left and right vision areas while reduce the crosstalk area as much as possible, the predetermined height is generally set to about 100 microns. When the display unit is a liquid crystal display, the liquid crystal display typically comprises red, green and blue (RGB) sub-pixels 72 (72-1, 72-2) and a color filter glass 71. In this case, the predetermined height h described above refers to the perpendicular distance between the upper surface of RGB sub-pixels 72 and the upper edge of the slit grating 80. However, in a practical production process, it is very difficult to produce a color filter glass of about 100 microns. Although it can be realized by reducing the thickness of a glass, this method is not suitable for automatic mass production.